The United States Conference of Catholic Bishops' pastoral letter on stewardship, Stewardship:  A Disciple's Response gives some insight into the characteristics that make up a good Christian steward.  It may not have the powers of a stewardship "profiler" or "mentalist", but it certainly gives us some tangible things to think about. 

The Christian steward should display some of the following traits:

Insight - Before the disciples could live what we know as the stewardship way of life, they needed a flash of insight, or a certain way of viewing the world and their relationship to it in a fresh light.  This "divine grandeur," more than anything else, is often what sets people on the path to Christian stewardship (Stewardship:  A Disciple's Response, 39).

Conscientiousness - Stewards are fully conscious of their accountability in sharing of their time, talent and treasure.  As caretakers of the gifts that God has given them, they have the opportunity and responsibility to use them to their fullest potential to spread God's kingdom on Earth (40).

Generosity - Christian stewards are generous out of love as well as duty.  They should display a desire to share with and care for others based on the sacramental graces they have received.  And they are also cognizant of the many warnings that the New Testament presents to those who fail in charity and authentic love (40).

Joy - Christian stewards are often presented with difficult obstacles, but they should remain joyful in the face of challenges to their lives of stewardship.  Like Paul, the good steward is able to say, "I am filled with encouragement, I am overflowing with joy all the more because of all our affliction" (2 Cor. 7:4).  Only by serving with a joyful spirit will stewards fully reap the rewards of their service, both in this life and the next.